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Contact the study team using the details below to take part. If there are no contact details below please ask your doctor in the first instance.
Dr
Surgical Interventions Trials Unit
(SITU)
+44 (0)1865 223464
endonet@nds.ox.ac.uk
Prof
Michael
Douek
+44 (0)1865 223492
michael.douek@nds.ox.ac.uk
Prof
Ramsey
Cutress
+44 (0)23 8120 6676
R.I.Cutress@soton.ac.uk
More information about this study, what is involved and how to take part can be found on the study website.
Newly diagnosed strongly ER-positive negative breast cancer
This information is provided directly by researchers and we recognise that it isn't always easy to understand. We are working with researchers to improve the accessibility of this information.
50,000 women develop breast cancer each year in the United Kingdom, mostly women after menopause and of a type known as oestrogen-receptor positive (ER+), HER-2 (human epidermal receptor-2) negative. The current usual standard treatment is surgery within a month of diagnosis, followed by radiotherapy for some where required, and anti-hormone therapy (known as endocrine therapy; ET) for 5-10 years. Most post-menopausal women with early breast cancer will not require chemotherapy. Almost one half will be treated by surgical removal of the breast (mastectomy). For others, lumpectomy (breast conservation surgery), enables a more limited amount of breast tissue to be removed and breast preservation. ET after surgery is very effective in the long-term treatment of breast cancer; it is however currently unknown whether it is also beneficial to start this same ET before surgery, known as neoadjuvant endocrine therapy (NET). This study is to determine whether giving some of the ET before surgery will shrink the tumour before operating. This could increase the rates of breast preservation by reducing the number of mastectomies for some women and the extent of surgery for others (removing less tissue leaves less defect). After mastectomy, many women do not want or are unsuitable for breast reconstruction. Even if received, this may not always fully compensate for breast removal. If it is shown that NET reduces the amount of breast tissue that has to be removed and increases the rates of breast preservation, this would be anticipated to improve cosmetic outcomes, leading to a better quality of life. This study therefore compares the traditional order of surgery within a month, to a period of pre-surgical ET followed by surgery.
Start dates may differ between countries and research sites. The research team are responsible for keeping the information up-to-date.
The recruitment start and end dates are as follows:
You can take part if:
Current participant inclusion criteria as of 04/10/2024:
Main study:
1. Female
2. Clinically post-menopausal, according to established local criteria, and suitable for an aromatase inhibitor
3. Strongly ER+; defined as Allred scores of 7 or 8 or equivalent*
4. Tumour size ≥15mm
5. Suitable for surgery and radiotherapy
6. Unifocal, newly diagnosed breast cancer visible on USS Note: Satellite lesions ≤5 mm and ≤10 mm in distance from the edge of the primary lesion are permitted as long as they can be removed en bloc;
7. Participant is able and willing to give informed consent for participation in the trial
8. In the Investigator's opinion, is able to comply with all trial requirements
* or equivalent may include a histochemical score (H-score) ≥ 200.
QRI (information study) Patients:
1. Patients approached for participation in the EndoNET study
2. Patient inclusions are the same as for the EndoNET study
Healthcare professionals (HCPs) and research personnel (RPs):
1. HCPs or RPs involved in management, operation or recruitment for the EndoNET study
2. Trial management group (TMG) members with a role in planning/coordinating recruitment
Current inclusion criteria as of 02/06/2023 to 04/10/2024:
Main study:
1. Female
2. Clinically post-menopausal; including one of:
2.1. Amenorrhoea >12 months and an intact uterus
2.2. Bilateral oophorectomy
2.3. For those with a history of hysterectomy, or hormone replacement therapy (HRT) within 12 months, venous FSH levels classified as post-menopausal by the testing laboratory if any doubt
3. Unifocal, newly diagnosed breast cancer visible on USS
4. Strongly ER+; defined as Allred scores of 7 or 8 or equivalent*
5. HER2- by immunohistochemistry, or 2+ and not amplified by in situ hybridisation
6. T-stage 1, 2 or 3 (≥15 mm)
7. Axillary N0-1 on diagnostic USS +/- negative fine-needle aspiration (FNA) or core biopsy
8. Suitable for surgery and radiotherapy
9. Chemotherapy unlikely to be indicated
10. Participant is able and willing to give informed consent for participation in the trial
11. In the Investigator's opinion, is able to comply with all trial requirements
* or equivalent may include a histochemical score (H-score) ≥ 200.
QRI (information study)
Patients:
1. Patients approached for participation in the EndoNET study
2. Patient inclusions are the same as for the EndoNET study
Healthcare professionals (HCPs) and research personnel (RPs):
1. HCPs or RPs involved in management,
You may not be able to take part if:
Current participant exclusion criteria as of 04/10/2024: Main study:The participant may not enter the trial if ANY of the following apply:1. Bilateral breast cancer2. cN3 disease3. cT4 disease Note: T4 is defined as (i) chest wall (rib/intercostal) involvement (adherence/invasion to pectoralis is NOT an extension to the chest wall and is not defined as T4 here) or (ii) skin ulceration, skin nodules or oedema such as in inflammatory breast cancer. Dimpling of the skin, nipple retraction or other skin other changes without ulceration, nodules or oedema, do not make a tumour T4;4. Metastatic breast cancer (Stage IV disease)5. Chemotherapy or anti-HER-2 therapy for current breast cancer started or planned at the time of randomisation6. Previous invasive malignancy within 5 years which is likely to affect the safety or efficacy assessment or compliance with the protocol or interpretation of results7. Concurrent use (at the time of randomisation) of HRT or any other oestrogen-containing medication (including vaginal oestrogens) Note: Presence of Mirena coil at the time of randomisation is not an exclusion;8. If clinically pre-menopausal, ovarian suppression/ablation for the purposes of trial entry is not permitted9. Aromatase inhibitor endocrine treatment following current breast cancer diagnosis taken for longer than 14 days at time of randomization.
QRI (information study):Patients:1. Patient exclusions are the same as for the EndoNET study2. Patient does not wish to have consultations recorded and/or participate in interview
HCPs and RPs:1. HCPs or RPs who do not wish to have consultations recorded and/or participate in interview
Previous participant exclusion criteria:Main study:The participant may not enter the trial if ANY of the following apply:1. Bilateral breast cancer2. ER- or HER2+3. Stage IV disease (distant metastasis)4. Previous neoadjuvant treatment for breast cancer5. Previous invasive malignancy within 5 years other than basal cell carcinoma6. Concurrent use (at the time of randomisation) of HRT or any other oestrogen-containing medication (including vaginal oestrogens)7. Ovarian suppression/ablation for the purposes of trial entry not permitted
QRI (information study):Patients:1. Patient exclusions are the same as for the EndoNET study2. Patient does not wish to have consultations recorded and/or participate in interview
HCPs and RPs:1. HCPs or RPs who do not wish to have consultations recorded and/or participate in interview
Below are the locations for where you can take part in the trial. Please note that not all sites may be open.
Dr
Surgical Interventions Trials Unit
(SITU)
+44 (0)1865 223464
endonet@nds.ox.ac.uk
Prof
Michael
Douek
+44 (0)1865 223492
michael.douek@nds.ox.ac.uk
Prof
Ramsey
Cutress
+44 (0)23 8120 6676
R.I.Cutress@soton.ac.uk
More information about this study, what is involved and how to take part can be found on the study website.
The study is sponsored by University of Oxford and funded by Health Technology Assessment Programme.
Your feedback is important to us. It will help us improve the quality of the study information on this site. Please answer both questions.
Or CPMS 52372
You can print or share the study information with your GP/healthcare provider or contact the research team directly.
